Top-mounted vehicle racks provide a versatile platform for transporting bicycles, skis, snowboards, boats, cargo boxes, gear racks, and other items. Such racks may include crossbars that extend side-to-side across the top of a vehicle. The crossbars typically are supported on each side of the vehicle's roof by a tower, where the length of each crossbar and the distance between crossbars depend on factors such as the shape and size of the vehicle's roof. The towers supporting the rack crossbars are securely fastened to the vehicle in some manner, to prevent the rack from slipping during use.
With the growing popularity of bicycling as a recreational activity, vehicles are often equipped with racks specifically configured to transport bicycles. Various systems have been developed to secure and stabilize bicycles on vehicle-mounted crossbars. One such system utilizes a fork block mounted to one of the bars with a skewer extending therethrough to receive and grip the front forks of a bicycle. Typically in such systems, a wheel tray extends from the fork block to the other crossbar to receive the rear tire of the bicycle. While these systems typically securely hold the bicycle in place, they have the disadvantage that the user must remove the front wheel of the bicycle before placing it in the rack, and then secure the front wheel separately to the rack or store it inside the vehicle.
Another common system used to attach a bicycle to vehicle-mounted crossbars secures both wheels of the bicycle to a wheel tray extending between the crossbars. This has the advantage that the user may secure the bicycle to the rack without removing the front wheel of the bicycle, but in such systems, a mechanism other than a fork block must be provided to secure the front end of the bicycle to the rack. Such mechanisms may include various combinations of straps, clamps, and stabilizing bars that attach to various points on the bicycle frame and/or wheels.
Frame attachment may effectively secure the bicycle to the vehicle rack. However, the rigidity of the bicycle frame may transfer potentially damaging motions from the vehicle to the bicycle. As a result, the frame may be damaged structurally. In addition, points of carrier engagement on the frame may be damaged cosmetically, that is, dented or scratched.
Wheel attachment overcomes some of the problems associated with frame attachment, because bicycle tires have an inherent shock-absorbing ability, which generally reduces the effects of sudden vehicle motions on an attached bicycle. However, some wheel-based carriers do not grip a bicycle wheel tightly enough to safely carry a bicycle on a vehicle roof at high speeds. Other wheel-based carriers are not designed for easy bicycle loading on a vehicle roof. As a result, it may be difficult for one person to position and balance a bicycle on the carrier as the bicycle is attached. Therefore, a vehicle-mounted bicycle carrier is needed that is easily loaded with a bicycle and that holds a wheel of the bicycle securely and effectively.